VIENNA - The UN nuclear watchdog is expected to make a new attempt early next week to advance a long-stymied investigation into suspicions that Tehran may have carried out atomic bomb research, diplomatic sources said on Friday.

They said the International Atomic Energy Agency and Iran were likely to meet again in the coming days to discuss IAEA requests for information about detonators that can, among other things, be used to set of a nuclear explosive device.

It could provide an opportunity for progress on a key issue ahead of a quarterly IAEA report on Iran's nuclear program, also due next week, which will be debated by the UN agency's 35-nation governing board at a meeting in early June. (Reuters)